Cake Balls Texture

Ok, I have made cake balls a couple of times, but they always end up so DENSE!! Is this normal?? I mean very very very dense. Having said that, I usually use mud cake (cause thats what is in the freezer).

Any ideas on how to lightenn them up?? a bit more cake-y rather than super-dense-fudge-like-that-gets-caught-in-your-teeth texture?

Not sure what the tool is but I have bought both the metal and plastic candy dipping tools (by Wilton, I think) and they just suck.... I use a plain old dinner fork, long tined variety and for me the trick is to invert.

Between that, proper draining and the temp of the chocolate, I have greatly reduced the amount of cakeballs with feet